What is the difference between passive and non-dynamic rigid bodies?
here you can find the subtle difference:

https://www.blenderguru.com/tutorials/quick-tutorial-make-a-wrecking-ball-with-rigid-body-physics/

It says:

"We want our chain to swing, so we need the top link of the chain to be stationary. Select it then go to the Physics panel and uncheck Dynamic. This is different to Passive, because it’s still using it’s Mesh collision data but it won’t move."